WATS 3D : An Interobserver Study of Barrett's Esophagus-Associated Dysplasia Among Gastrointestinal Pathologists

INTRODUCTION

Wide-area transepithelial sampling with 3-dimensional computer-assisted analysis (WATS 3D ) has been shown to increase the detection rate of dysplasia (and intestinal metaplasia) in patients with Barrett's esophagus (BE). The purpose of this study was to evaluate the interobserver variability and accuracy of diagnosing BE-associated dysplasia in WATS 3D specimens among gastrointestinal (GI) pathologists without prior experience with this technology.

METHODS

Five GI pathologists underwent a 4-hour in-person (at microscope) and virtual training session and then evaluated digital images of discrete cellular foci from 60 WATS 3D cases with BE (20 nondysplastic BE [NDBE], 20 low-grade dysplasia [LGD], and 20 high-grade dysplasia/esophageal adenocarcinoma [HGD/EAC]). Each case consisted of 1 hematoxylin and eosin-stained image (cell block), and 1 liquid cytology or papanicolaou-stained smear image (120 images in total).

RESULTS

The overall kappa value among the 5 study pathologists was excellent (overall kappa = 0.93; kappa = 0.93 and 0.97 for cell block and smear specimens, respectively). There were no significant differences noted in kappa values in interpretation of the cell block vs smear specimens or in any of the individual diagnostic categories when the latter were evaluated separately. Furthermore, agreement was perfect (100%) regarding detection of neoplasia (either LGD, HGD, or EAC). Diagnoses were made with complete confidence in 91% of instances.

DISCUSSION

We conclude that GI pathologists, without any prior experience in interpretation of WATS 3D specimens, can undergo a short training session and then diagnose these specimens with a very high level of accuracy and reproducibility.

An Automated Tissue Systems Pathology Test Can Standardize the Management and Improve Health Outcomes for Patients With Barrett's Esophagus

INTRODUCTION

Low-grade dysplasia (LGD) in Barrett's esophagus (BE) is associated with an increased risk of progression to high-grade dysplasia or esophageal adenocarcinoma. However, because of substantial interobserver variability in the diagnosis of LGD, a patient's management plan and health outcome depend largely on which pathologist reviews their case. This study evaluated the ability of a tissue systems pathology test that objectively risk stratifies patients with BE (TissueCypher, TSP-9) to standardize management in a manner consistent with improved health outcomes for patients with BE.

METHODS

A total of 154 patients with BE with community-based LGD from the prospectively followed screening cohort of the SURF trial were studied. Management decisions were simulated 500 times with varying generalist (n = 16) and expert (n = 14) pathology reviewers to determine the most likely care plan with or without use of the TSP-9 test for guidance. The percentage of patients receiving appropriate management based on the known progression/nonprogression outcomes was calculated.

RESULTS

The percentage of patients with 100% of simulations resulting in appropriate management significantly increased from 9.1% for pathology alone, to 58.4% when TSP-9 results were used with pathology, and further increased to 77.3% of patients receiving appropriate management when only TSP-9 results were used. Use of the test results also significantly increased the consistency of management decisions for patients when their slides were reviewed by different pathologists ( P < 0.0001).

DISCUSSION

Management guided by the TSP-9 test can standardize care plans by increasing the early detection of progressors who can receive therapeutic interventions, while also increasing the percentage of nonprogressors who can avoid unnecessary therapy and be managed by surveillance alone.

A Tissue Systems Pathology Test Outperforms the Standard-of-Care Variables in Predicting Progression in Patients With Barrett's Esophagus

INTRODUCTION

Objective risk stratification is needed for patients with Barrett's esophagus (BE) to enable risk-aligned management to improve health outcomes. This study evaluated the predictive performance of a tissue systems pathology [TSP-9] test (TissueCypher) vs current clinicopathologic variables in a multicenter cohort of patients with BE.

METHODS

Data from 699 patients with BE from 5 published studies on the TSP-9 test were evaluated. Five hundred nine patients did not progress during surveillance, 40 were diagnosed with high-grade dysplasia/esophageal adenocarcinoma (HGD/EAC) within 12 months, and 150 progressed to HGD/EAC after 12 months. Age, sex, segment length, hiatal hernia, original and expert pathology review diagnoses, and TSP-9 risk classes were collected. The predictive performance of clinicopathologic variables and the TSP-9 test was compared, and the TSP-9 test was evaluated in clinically relevant patient subsets.

RESULTS

The sensitivity of the TSP-9 test in detecting progressors was 62.3% compared with 28.3% for expert-confirmed low-grade dysplasia (LGD), while the original diagnosis abstracted from medical records did not provide any significant risk stratification. The TSP-9 test identified 57% of progressors with nondysplastic Barrett's esophagus (NDBE) ( P < 0.0001). Patients with NDBE who scored TSP-9 high risk progressed at a similar rate (3.2%/yr) to patients with expert-confirmed LGD (3.7%/yr). The TSP-9 test provided significant risk stratification in clinically low-risk patients (NDBE, female, short-segment BE) and clinically high-risk patients (IND/LGD, male, long-segment BE) ( P < 0.0001 for comparison of high-risk classes vs low-risk classes).

DISCUSSION

The TSP-9 test predicts risk of progression to HGD/EAC independently of current clinicopathologic variables in patients with BE. The test provides objective risk stratification results that may guide management decisions to improve health outcomes for patients with BE.

Clinical and Endoscopic Differences Between Patients With Barrett's Esophagus With and Without Dysplasia/Adenocarcinoma

INTRODUCTION

Barrett's esophagus (BE) is the main precursor of esophageal adenocarcinoma (EAC). This study aimed to identify the risk factors associated with BE progression to dysplasia or EAC in a Latin population.

METHODS

The study is a retrospective analysis of a single-center cohort of patients with BE, evaluated from 2002 to 2012.

RESULTS

We identified 420 patients with BE; 281 (66.9%) of them were men with a mean age of 57.2 ± 15.3 years. Among all BE patients evaluated, 81 (19.3%) had progression to some degree of dysplasia/EAC. The mean follow-up was 5.6 years. Multivariate analysis showed that age (OR = 1.03), cigarette smoking (OR = 3.05), long-segment BE (OR = 4.81), and a visible lesion on BE (OR = 6.94) were associated with progression to dysplasia/EAC.

CONCLUSION

In Latin patients with BE, age, cigarette smoking, long-segment BE, and the presence of lesions were associated with the presence of dysplasia/EAC.

Artificial Intelligence in the Detection of Barrett's Esophagus: A Systematic Review

Barrett's esophagus (BE) remains a significant precursor to esophageal adenocarcinoma, requiring accurate and efficient diagnosis and management. The increasing application of machine learning (ML) technologies presents a transformative opportunity for diagnosing and treating BE. This systematic review evaluates the effectiveness and accuracy of machine learning technologies in BE diagnosis and management by conducting a comprehensive search across PubMed, Scopus, and Web of Science databases up to the year 2023. The studies were organized into five categories: computer-aided systems, natural language processing and text-based systems, deep learning on histology and biopsy images, real-time and video analysis, and miscellaneous studies. Results indicate high sensitivity and specificity across machine learning applications. Specifically, computer-aided systems showed sensitivities ranging from 84% to 100% and specificities from 64% to 90.7%. Natural language processing and text-based systems achieved an accuracy as high as 98.7%. Deep learning techniques applied to histology and biopsy images displayed sensitivities up to greater than 90% and a specificity of 100%. Furthermore, real-time and video analysis technologies demonstrated high performance with assessment speeds of up to 48 frames per second (fps) and a mean average precision of 75.3%. Overall, the reviewed literature underscores the growing capability and efficiency of machine learning technologies in diagnosing and managing Barrett's esophagus, often outperforming traditional diagnostic methods. These findings highlight the promising future role of machine learning in enhancing clinical practice and improving patient care for Barrett's esophagus.

Barrett's Esophagus in Rubinstein-Taybi Syndrome

Rubinstein-Taybi syndrome (RSTS; Online Mendelian Inheritance in Man^® [OMIM^®] #180849, #613684; Orpha: 783 ) is a rare plurimalformative autosomal dominant genetic disorder that affects one in 100,000-125,000 newborns with equal male and female distribution. It is characterized by distinctive facial features, short stature, broad and often angulated thumbs and halluces, and moderate-to-severe intellectual disability. In addition to ocular, cardiac, renal, endocrinologic, neurological, and psychomotor abnormalities, RSTS individuals can present with several gastrointestinal symptoms such as feeding difficulties, gastroesophageal reflux, and constipation. Currently, therapeutic strategies for RSTS involves a multi-disciplinary approach focusing mainly on symptomatic management. Here, we present a case of young-onset Barrett's esophagus in a patient with Rubinstein-Taybi syndrome.

Seattle protocol vs narrow band imaging guided biopsy in screening of Barrett's esophagus in gastroesophageal reflux disease patients

Barrett's esophagus has 0.5% to 7% risk of progression to esophageal adenocarcinoma. The method of obtaining biopsies to diagnose Barrett's is challenging. Seattle protocol has been considered as the gold standard, however its difficulty limits its applicability in practice. Narrow band imaging guided biopsy has been proposed as an alternative.To investigate the accuracy, sensitivity, specificity and applicability of Narrow band guided biopsy as a screening tool for Barret's esophagus in gastroesophageal reflux patients.Endoscopy was done in 2 different sessions 2 weeks apart for 100 patients in Alexandria, Egypt. Patients had at least one of the following: Chronic Gastroesophageal reflux disease, frequent Gastroesophageal reflux disease, or two or more risk factors for Barrett's esophagus. All patients with known Barrett's esophagus were excluded.Seventeen patients had Barrett's esophagus either by one of the two techniques or by both, 4 patients by both methods, 7 patients by narrow band imaging alone and 6 patients by Seattle protocol alone (P < .001, κ = 0.461). Sensitivity, specificity, negative predictive value and positive predictive value for Seattle protocol were 58.8%, 100%, 92.2%, 100% vs 76.5%, 100%, 95.4%, 100% respectively for narrow band imaging. A mean of 7.73 samples/patient was taken in Seattle protocol vs 3.42 samples in narrow band imaging (P < .001). A mean of 8.63 minutes was consumed in Seattle protocol vs 2.65 minutes in narrow band imaging (P < .001).Narrow band imaging guided biopsy might have higher accuracy, sensitivity and negative predictive value as well as fewer number of biopsies and shorter time of the procedure compared to Seattle protocol which might increases its applicability as screening protocol for Barrett's esophagus. However, further larger multicentric studies are needed.

A crosssectional analysis of Facebook comments to study public perception of a new diagnostic test called the Cytosponge

Social media provides a useful platform for informal discussions about healthcare. Acceptability is key to the uptake of diagnostic devices and this can be difficult to gauge from questionnaires and qualitative studies. The aim of this study is to investigate whether Facebook could be used to gauge public perception toward uptake of a new diagnostic test for Barrett's esophagus called the Cytosponge. We retrospectively reviewed Facebook comments relating to a video on the Cytosponge. We categorized comments into: (1) Positive, (2) Negative, (3) Unknown and (4) Questions. Recurring themes that arose were compared to a qualitative study on the Cytosponge. The video received 22.5 million views and 2837 comments within four months. Of these, 525 comments were positive, 215 were unknown, 179 were negative, 71 were questions, and 1847 were 'Tagged' comments. Among positive comments, recurrent themes were that it was innovative, could lead to early cancer-detection, and more favorable than endoscopy. Among negative comments, a recurring theme was concern about the risk of gagging and vomiting. Among 'questions', a recurring theme was related to the risk of Cytosponge detachment. We compared our analysis to a published qualitative study and found similar themes arose across both studies. Facebook provides a rich source of qualitative data, which could be used to augment studies to gauge public perception toward a new diagnostic test.

A biomarker panel predicts progression of Barrett's esophagus to esophageal adenocarcinoma

Progression from Barrett's esophagus (BE) to esophageal adenocarcinoma (EAC) is uncommon but the consequences are serious. Predictors of progression are essential to optimize resource utilization. This study assessed the utility of a promising panel of biomarkers applicable to routine paraffin embedded biopsies (FFPE) to predict progression of BE to EAC in a large population-based, nested case-control study.We utilized the Amsterdam-based ReBus nested case-control cohort. BE patients who progressed to high-grade dysplasia (HGD)/EAC (n = 130) and BE patients who never progressed (n = 130) were matched on age, sex, length of the BE segment, and duration of endoscopic surveillance. All progressors had minimum 2 years of endoscopic surveillance without HGD/EAC to exclude prevalent neoplasia. We assessed abnormal DNA content, p53, Cyclin A, and Aspergillus oryzae lectin (AOL) in FFPE sections. We performed conditional logistic regression analysis to estimate odds ratio (OR) of progression based on biomarker status.Expert LGD (OR, 8.3; 95% CI, 1.7-41.0), AOL (3 vs. 0 epithelial compartments abnormal; OR, 3.6; 95% CI, 1.2-10.6) and p53 (OR, 2.3; 95% CI, 1.2-4.6) were independently associated with neoplastic progression. Cyclin A did not predict progression and DNA ploidy analysis by image cytometry was unsuccessful in the majority of cases, both were excluded from the multivariate analysis. The multivariable biomarker model had an area under the receiver operating characteristic curve of 0.73.Expert LGD, AOL, and p53 independently predict neoplastic progression in BE patients and are applicable to routine practice. These biomarkers can aid in selecting patients for endoscopic ablation or more intensive surveillance.

Dysplasia severity is associated with poor quality of life in patients with Barrett's esophagus referred for endoscopic eradication therapy

Limited data exist regarding patient-reported outcomes and quality of life (QOL) experienced by patients with Barrett's esophagus (BE) referred for endoscopic eradication therapy (EET). Specifically, the impact of grade of dysplasia has not been explored. The purpose of this study is to measure patient-reported symptoms and QOL and identify factors associated with poor QOL in BE patients referred for EET. This was a prospective multicenter study conducted from January 2015 to October 2017, which included patients with BE referred for EET. Participants completed a set of validated questionnaires to measure QOL, symptom severity, and psychosocial factors. The primary outcome was poor QOL defined by a PROMIS score >12. Multivariable logistic regression analysis was performed to identify factors associated with poor QOL. In total, 193 patients participated (mean age 64.6 years, BE length 5.5 cm, 82% males, 92% Caucasians) with poor QOL reported in 104 (53.9%) participants. On univariate analysis, patients with poor QOL had lower use of twice daily proton pump inhibitor use (61.5% vs. 86.5%, P = 0.03), shorter disease duration (4.9 vs. 5.9 years, P = 0.04) and progressive increase in grade of dysplasia (high-grade dysplasia: 68.8% vs. 31.3%, esophageal adenocarcinoma: 75.5% vs. 24.5%, P < 0.001). Multivariate analysis demonstrated that high-grade dysplasia was independently associated with poor QOL (OR: 5.57, 95% CI: 1.05, 29.5, P = 0.04). In summary, poor QOL is experienced by the majority of patients with BE referred for EET and the degree of dysplasia was independently associated with poor QOL, which emphasizes the need to incorporate patient-centered outcomes when studying treatment of BE-related dysplasia.

Validation of a biomarker panel in Barrett's esophagus to predict progression to esophageal adenocarcinoma

In a prior study, baseline mutational load (ML) predicted progression to high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC) in Barrett's esophagus (BE) with an area under the curve (AUC) of 0.95. We aimed to validate the test characteristics of this predictive biomarker panel using crude DNA lysates in a larger well-characterized cohort. We performed a nested case-control study of BE patients from three tertiary referral centers in the Netherlands. Cases had baseline nondysplastic BE (NDBE) and developed HGD/EAC ≥ 2 years later. Controls were matched 2:1, had baseline NDBE, and no progression. Polymerase chain reaction (PCR)-based mutational analysis was performed on crude lysates from formalin-fixed, paraffin-embedded tissue. ML was calculated from loss of heterozygosity (LOH) and microsatellite instability (MSI) at 10 genomic loci. Receiver operator characteristic (ROC) curves were created to assess the diagnostic utility of various cutoffs of ML for progression. Of 159 subjects, 58 were progressors and 101 were nonprogressors, there was no difference in mean ML in preprogression tissue in progressors and nonprogressors (ML = 0.73 ± 0.69 vs. ML = 0.74 ± 0.61, P = 0.93). ROC curves showed poor discrimination of ML in predicting progression with AUC of 0.50 at ML ≥ 1. AUC did not vary with different ML cut-points. The utility of the ML to stratify BE patients for risk of progression was not confirmed in this study. The etiology for discrepancies between this and prior studies showing high predictiveness is likely due to the use of crude lysates in this study, but requires further investigation.

Association of sporadic and familial Barrett's esophagus with breast cancer

Barrett's esophagus (BE) is the only known precursor to esophageal adenocarcinoma (EAC). Based on striking aggregation of breast cancer and BE/EAC within families as well as shared risk factors and molecular mechanisms of carcinogenesis, we hypothesized that BE may be associated with breast cancer. Pedigree analysis of families identified prospectively at multiple academic centers as part of the Familial Barrett's Esophagus Consortium (FBEC) was reviewed and families with aggregation of BE/EAC and breast cancer are reported. Additionally, using a matched case-control study design, we compared newly diagnosed BE cases in Caucasian females with breast cancer (cases) to Caucasian females without breast cancer (controls) who had undergone upper endoscopy (EGD). Two familial pedigrees, meeting a stringent inclusion criterion, manifested familial aggregation of BE/EAC and breast cancer in an autosomal dominant inheritance pattern with incomplete penetrance. From January 2008 to October 2016, 2812 breast cancer patient charts were identified, of which 213 were Caucasian females who underwent EGD. Six of 213 (2.82%) patients with breast cancer had pathology-confirmed BE, compared to 1 of 241 (0.41%) controls (P-value < 0.05). Selected families with BE/EAC show segregation of breast cancer. A breast cancer diagnosis is marginally associated with BE. We postulate a common susceptibility between BE/EAC and breast cancer.

Considering the esophagogastric junction as a 'zone'

Siewert's classification of adenocarcinoma of the esophagogastric junction (EGJ) classifies tumors anatomically for determining the appropriate surgical technique. According to this classification, a type II tumor, true carcinoma of the cardia, is defined as a cancer within 1 cm proximal to 2 cm distal of the EGJ. Histological analysis indicates that the cardiac gland is present with a high degree of frequency between 1-2 cm to the gastric side and 1-2 cm to the esophageal side of the EGJ, which means that this zone can be considered as neither the stomach nor the esophagus but rather as a third zone known as the 'EGJ zone'. It has been suggested that there are multiple causes for development of adenocarcinoma in the EGJ zone. The TNM Classification of Malignant Tumours 7th Edition considers EGJ adenocarcinoma (EGJAC) occurring in the EGJ zone to be a part of esophageal adenocarcinoma (EAC). However, recent studies have indicated that EGJAC behaves differently from EAC and gastric carcinoma. Barrett's esophagus is now considered an important factor in the etiology of EGJAC, but, as yet, no studies have elucidated the differences between cancer arising from short-segment Barrett's esophagus and cancer of the gastric cardia. Thus, there is currently no clinical relevance to subdivision of adenocarcinoma in the EGJ zone into above or below the EGJ line.

Rates and predictors of progression to esophageal carcinoma in a large population-based Barrett's esophagus cohort

BACKGROUND AND AIMS

Rates of progression to esophageal adenocarcinoma in subjects with Barrett's esophagus (BE) are lower than previously estimated. Identification of predictors of progression will enable risk stratification of BE subjects, potentially making current surveillance programs more efficient. We aimed to assess the potential of demographic and lifestyle factors, obesity, and medications in predicting progression in BE.

METHODS

BE subjects were identified from the General Practice Research Database using validated diagnostic codes. BE subjects developing esophageal cancer (EC) 12 months after their index BE diagnosis were defined as progressors. Time-to-event analysis was used to assess the overall risk of progression to EC. Cox proportional hazards models and time-varying marginal structural models were used to assess predictors of progression.

RESULTS

Included in the analysis were 9660 BE patients. The mean age (SD) of the study subjects was 63 (13.5) years; 62.6% were men. One hundred three subjects (1.1%) progressed to EC. The mean (SD) follow-up since initial diagnosis was 4.8 (3.3) years. The incidence of EC was 2.23 per 1000 person-years of follow-up. Increasing age, male gender, and being overweight (body mass index, 25-29.9) were found to be independent predictors of progression. When time-varying models were used, proton pump inhibitor (PPI) and statin use were protective against progression.

CONCLUSIONS

In this large population-based cohort of patients with BE, increasing age, male gender, and being overweight predicted progression to EC, whereas PPI and statin use were protective against EC development. These factors may aid in developing a risk score to predict the risk of progression and chemopreventive strategies in patients with BE.

Risk of malignant progression in Barrett's esophagus indefinite for dysplasia

Barrett's esophagus is a well-recognized risk factor for esophageal adenocarcinoma. The natural history of Barrett's esophagus classified as ‘indefinite for dysplasia’ (IND) is poorly characterized. The aim of this study is to characterize the natural history of IND by determining the rate of neoplastic progression and identifying risk factors for progression. Patients from the University of Pennsylvania Health System pathology database and Barrett's esophagus registry with a diagnosis of IND between 2000 and 2014 were identified. Exclusion criteria included: (1) prior diagnosis of low-grade dysplasia (LGD), high-grade dysplasia (HGD), or esophageal adenocarcinoma (EAC); (2) presence of LGD, HGD, or EAC at the time of diagnosis of IND; and (3) lack of follow-up endoscopy after diagnosis. Patients with neoplastic progression were classified as having either prevalent disease (LGD, HGD, or EAC on surveillance biopsy within 12 months of IND diagnosis) or incident disease (LGD, HGD, or EAC on surveillance biopsy >12 months after IND diagnosis). One hundred six patients were eligible for analysis. Of 87 patients with follow-up endoscopy and biopsies within 1 year of IND diagnosis, 7 (8%) had prevalent disease (2 LGD, 4 HGD, 1 EAC). The prevalence of LGD was 2.3%, HGD was 4.6%, and EAC was 1.1%. Importantly, four of the seven prevalent (2 LGD, 2 HGD) cases were found to have dysplasia within 6 months of IND diagnosis. No demographic or endoscopic characteristics studied were associated with prevalent disease. Of the 106 IND patients, there were 66 patients without prevalent dysplasia with >1-year follow-up. Three (4.5%) progressed (1 to LGD after 12 months, 2 to HGD after 16.5 and 28 months), yielding an incidence rate for any dysplasia of 1.4 cases/100 person-years and HGD/EAC of 0.9/100 person-years. Risk factors for incident disease were smoking (p = 0.02) and Barrett's esophagus segment length (p = 0.03). IND is associated with considerable risk of prevalent dysplasia, especially within the first 6 months after diagnosis. However, the incidence of HGD/EAC is low and similar to previous studies of IND. These data suggest that IND patients should have repeat endoscopy within 6 months with careful surveillance protocols. Longer BE length and smoking history may help predict which patients are more likely to develop dysplasia, and therefore identify patients who may warrant even closer monitoring.

Targeting chemokine pathways in esophageal adenocarcinoma

Esophageal adenocarcinoma (EAC) is one of the fastest growing malignancies in the US and needs newer therapeutic and diagnostic strategies. Chronic inflammation plays a role in the pathogenesis of EAC and contributes to the dysplastic conversion of normal esophageal epithelium to Barrett's esophagus and frank adenocarcinoma. Chemokines play important roles in mediating inflammation and recent evidence implicates these ligands and their receptors in the development and spread of various tumors. We demonstrated that the chemokines IL8, CXCL1 and CXCL3 are significantly overexpressed during esophageal carcinogenesis and accompanied by amplification and demethylation of the chr4q21 gene locus. We also demonstrated that IL8 levels can be detected in serum of patients with EAC and can serve as potential biomarkers. We now demonstrate that inhibition of IL8 receptor, CXCR2, leads to decreased invasiveness of esophageal adenocarcinoma derived cells without affecting cellular proliferation. Taken together, these studies reveal the important roles that chemokines play in development of esophageal cancer and demonstrate that these pathways can serve as potential therapeutic targets.

Oral bisphosphonates and upper gastrointestinal toxicity: a study of cancer and early signals of esophageal injury

SUMMARY

We evaluated the association between bisphosphonate use and (1) upper gastrointestinal cancer, (2) upper endoscopy, (3) incident Barrett's esophagus, and (4) prescription antacid initiation among Medicare beneficiaries. We found no bisphosphonate-cancer association and negative bisphosphonate-Barrett's association.

INTRODUCTION

Bisphosphonates can irritate the esophagus; a cancer association has been suggested. Widespread bisphosphonates use compels continued investigation of upper gastrointestinal toxicity.

METHODS

Using a 40% Medicare random sample denominator, inpatient, outpatient (2003-2011), and prescription (2006-2011) claims, we studied patients age 68 and older with osteoporosis and/or oral bisphosphonate use. Inverse propensity weighting estimated marginal structural models for the effect of bisphosphonate intensity (pills per month) and cumulative bisphosphonate pills received on upper gastrointestinal cancer risk. Secondary analyses of sub-cohorts without past bisphosphonates or upper endoscopy assessed bisphosphonate initiation and risk of (1) upper endoscopy, (2) incident Barrett's esophagus, and (3) prescription antacid initiation.

RESULTS

The cohort included 1.64 million beneficiaries: 87.9% women, mean age, 76.8 (standard deviation (SD) 9.3); mean follow-up, 39.6 months; 38.1% received oral bisphosphonates. Cumulative bisphosphonate receipt, among users, ranged from 4 to 252 pills (5th to 95th percentile). We identified 2,308 upper gastrointestinal cancers (0.43/1000 person years). We found no association between cumulative bisphosphonate pills and cancer, odds ratio (OR) for each additional pill 1.00 (95% confidence interval (CI) 1.00, 1.00). In sub-cohorts, compared to none, lowest cumulative bisphosphonate use (one to nine pills) was associated with higher risk of endoscopy (OR 1.11, 95% CI 1.08-1.14) and antacid initiation (OR 1.13, 95% CI 1.10-1.16); higher intensity conferred no increased risk. Higher intensity and higher cumulative bisphosphonate category were associated with lower Barrett's risk.

CONCLUSIONS

We found no bisphosphonate-cancer association and negative bisphosphonate-Barrett's association. Bisphosphonate initiation appears to identify patients susceptible to early irritating effects; clinicians might offer alternatives and delay endoscopy or antacids.

A randomized comparative effectiveness trial of novel endoscopic techniques and approaches for Barrett's esophagus screening in the community

OBJECTIVES

The objective of this study was to compare participation rates and clinical effectiveness of sedated esophagogastroduodenoscopy (sEGD) and unsedated transnasal endoscopy (uTNE) for esophageal assessment and Barrett's esophagus (BE) screening in a population-based cohort.

METHODS

This was a prospective, randomized, controlled trial in a community population. Subjects ≥50 years of age who previously completed validated gastrointestinal symptom questionnaires were randomized (stratified by age, sex, and reflux symptoms) to one of three screening techniques (either sEGD or uTNE in a mobile research van (muTNE) or uTNE in a hospital outpatient endoscopy suite (huTNE)) and invited to participate.

RESULTS

Of the 459 subjects, 209 (46%) agreed to participate (muTNE n=76, huTNE n=72, and sEGD n=61). Participation rates were numerically higher in the unsedated arms of muTNE (47.5%) and huTNE (45.7%) compared with the sEGD arm (40.7%), but were not statistically different (P=0.27). Complete evaluation of the esophagus was similar using muTNE (99%), huTNE (96%), and sEGD (100%) techniques (P=0.08). Mean recovery times (min) were longer for sEGD (67.3) compared with muTNE (15.5) and huTNE (18.5) (P<0.001). Approximately 80% of uTNE subjects were willing to undergo the procedure again in future. Respectively, 29% and 7.8% of participating subjects had esophagitis and BE.

CONCLUSIONS

Mobile van and clinic uTNE screening had comparable clinical effectiveness with similar participation rates and safety profile to sEGD. Evaluation time with uTNE was significantly shorter. Prevalence of BE and esophagitis in community subjects ≥50 years of age was substantial. Mobile and outpatient unsedated techniques may provide an effective alternative strategy to sEGD for esophageal assessment and BE screening.

Transcribed ultraconserved noncoding RNAs (T-UCR) are involved in Barrett's esophagus carcinogenesis

Barrett's esophagus (BE) involves a metaplastic replacement of native esophageal squamous epithelium (Sq) by columnar-intestinalized mucosa, and it is the main risk factor for Barrett-related adenocarcinoma (BAc). Ultra-conserved regions (UCRs) are a class non-coding sequences that are conserved in humans, mice and rats. More than 90% of UCRs are transcribed (T-UCRs) in normal tissues, and are altered at transcriptional level in tumorigenesis. To identify the T-UCR profiles that are dysregulated in Barrett's mucosa transformation, microarray analysis was performed on a discovery set of 51 macro-dissected samples obtained from 14 long-segment BE patients. Results were validated in an independent series of esophageal biopsy/surgery specimens and in two murine models of Barrett's esophagus (i.e. esophagogastric-duodenal anastomosis). Progression from normal to BE to adenocarcinoma was each associated with specific and mutually exclusive T-UCR signatures that included up-regulation of uc.58-, uc.202-, uc.207-, and uc.223- and down-regulation of uc.214+. A 9 T-UCR signature characterized BE versus Sq (with the down-regulation of uc.161-, uc.165-, and uc.327-, and the up-regulation of uc.153-, uc.158-, uc.206-, uc.274-, uc.472-, and uc.473-). Analogous BE-specific T-UCR profiles were shared by human and murine lesions. This study is the first demonstration of a role for T-UCRs in the transformation of Barrett's mucosa.

High definition endoscopy and "narrow band imaging" in the diagnosis of gastroesophageal reflux disease

INTRODUCTION

The gastroesophageal reflux disease is a common condition in the western world but less than half of patients present endoscopic abnormalities, making a standard procedure unsuitable for diagnosis. High definition endoscopy coupled with narrow band imaging has shown potential for differentiation of lesions and possible biopsy, allowing early diagnosis and treatment.

METHODS

This review describes the principles of biotic and their influence in obtaining images with better definition of the vessels in the mucosa, through the narrow band imaging. Selected papers using it in patients with reflux disease and Barrett's esophagus are analyzed in several ways, highlighting the findings and limitations.

CONCLUSION

The meaning of the narrow band imaging in the endoscopic diagnosis of reflux disease will be defined by large scale studies, with different categories of patients, including assessment of symptoms and response to treatment.

Modeling inflammation and oxidative stress in gastrointestinal disease development using novel organotypic culture systems

Gastroesophageal reflux disease (GERD), Barrett's esophagus (BE), graft-versus-host disease (GVHD), and inflammatory bowel diseases such as ulcerative colitis and Crohn's disease are common human gastrointestinal diseases that share inflammation as a key driver for their development. A general outcome resulting from these chronic inflammatory conditions is increased oxidative stress. Oxidative stress is caused by the generation of reactive oxygen and nitrogen species that are part of the normal inflammatory response, but are also capable of damaging cellular DNA, protein, and organelles. Damage to DNA can include DNA strand breaks, point mutations due to DNA adducts, as well as alterations in methylation patterns leading to activation of oncogenes or inactivation of tumor suppressors. There are a number of significant long-term consequences associated with chronic oxidative stress, most notably cancer. Infiltrating immune cells and stromal components of tissue including fibroblasts contribute to dynamic changes occurring in tissue related to disease development. Immune cells can potentiate oxidative stress, and fibroblasts have the capacity to contribute to advanced growth and proliferation of the epithelium and any resultant cancers. Disease models for GERD, BE, GVHD, and ulcerative colitis based on three-dimensional human cell and tissue culture systems that recapitulate in vivo growth and differentiation in inflammatory-associated microphysiological environments would enhance our understanding of disease progression and improve our ability to test for disease-prevention strategies. The development of physiologically relevant, human cell-based culture systems is therefore a major focus of our research. These novel models will be of enormous value, allowing us to test hypotheses and advance our understanding of these disorders, and will have a translational impact allowing us to more rapidly develop therapeutic and chemopreventive agents. In summary, this work to develop advanced human cell-based models of inflammatory conditions will greatly improve our ability to study, prevent, and treat GERD, BE, GVHD, and inflammatory bowel disease. The work will also foster the development of novel therapeutic and preventive strategies that will improve patient care for these important clinical conditions.

Interobserver agreement for the detection of Barrett's esophagus with optical frequency domain imaging

BACKGROUND

Optical frequency domain imaging (OFDI) is a second-generation form of optical coherence tomography (OCT) providing comprehensive cross-sectional views of the distal esophagus at a resolution of ~7 μm.

AIM

Using validated OCT criteria for squamous mucosa, gastric cardia mucosa, and Barrett's esophagus (BE), the objective of this study was to determine the inter- and intra-observer agreements by a large number of OFDI readers for differentiating these tissues.

METHODS

OFDI images were obtained from nine subjects undergoing screening and surveillance for BE. Sixty-four OFDI image regions of interest were randomly selected for review. A training set of 19 images was compiled distinguishing squamous mucosa from gastric cardia and BE using previously validated OCT criteria. The ten readers then interpreted images in a test set of 45 different images of squamous mucosa (n = 15), gastric cardia (n = 15), or BE (n = 15). Interobserver agreement differentiating the three tissue types and BE versus non-BE mucosa was determined using multi-rater Fleiss's κ value. The images were later randomized again and four readers repeated the test 3 weeks later to assess intraobserver reliability.

RESULTS

All ten readers showed excellent agreement for the differentiation of BE versus non-BE mucosa (κ = 0.811 p < 0.0001) and for differentiating BE versus gastric cardia versus squamous mucosa (κ = 0.866, p < 0.0001). For the four readers who repeated the test, the median intraobserver agreement (BE vs. non-BE) was high (κ = 0.975, IQR: 0.94, 1.0).

CONCLUSIONS

Trained readers have a high interobserver agreement for differentiating BE, squamous, and gastric cardia mucosa using OFDI.

Structural markers observed with endoscopic 3-dimensional optical coherence tomography correlating with Barrett's esophagus radiofrequency ablation treatment response (with videos)

BACKGROUND

Radiofrequency ablation (RFA) is effective for treating Barrett's esophagus (BE) but often involves multiple endoscopy sessions over several months to achieve complete response.

OBJECTIVE

Identify structural markers that correlate with treatment response by using 3-dimensional (3-D) optical coherence tomography (OCT; 3-D OCT).

DESIGN

Cross-sectional.

SETTING

Single teaching hospital.

PATIENTS

Thirty-three patients, 32 male and 1 female, with short-segment (<3 cm) BE undergoing RFA treatment.

INTERVENTION

Patients were treated with focal RFA, and 3-D OCT was performed at the gastroesophageal junction before and immediately after the RFA treatment. Patients were re-examined with standard endoscopy 6 to 8 weeks later and had biopsies to rule out BE if not visibly evident.

MAIN OUTCOME MEASUREMENTS

The thickness of BE epithelium before RFA and the presence of residual gland-like structures immediately after RFA were determined by using 3-D OCT. The presence of BE at follow-up was assessed endoscopically.

RESULTS

BE mucosa was significantly thinner in patients who achieved complete eradication of intestinal metaplasia than in patients who did not achieve complete eradication of intestinal metaplasia at follow-up (257 ± 60 μm vs 403 ± 86 μm; P < .0001). A threshold thickness of 333 μm derived from receiver operating characteristic curves corresponded to a 92.3% sensitivity, 85% specificity, and 87.9% accuracy in predicting the presence of BE at follow-up. The presence of OCT-visible glands immediately after RFA also correlated with the presence of residual BE at follow-up (83.3% sensitivity, 95% specificity, 90.6% accuracy).

LIMITATIONS

Single center, cross-sectional study in which only patients with short-segment BE were examined.

CONCLUSION

Three-dimensional OCT assessment of BE thickness and residual glands during RFA sessions correlated with treatment response. Three-dimensional OCT may predict responses to RFA or aid in making real-time RFA retreatment decisions in the future.

Targeting the intrinsic inflammatory pathway: honokiol exerts proapoptotic effects through STAT3 inhibition in transformed Barrett's cells

One way to link chronic inflammation with cancer is through the intrinsic inflammatory pathway, in which genetic alterations that induce malignant transformation also produce a cancer-promoting, inflammatory microenvironment. Signal transducer and activator of transcription 3 (STAT3) contributes to the intrinsic inflammatory pathway in Barrett's esophagus. In human tumors, honokiol (a polyphenol in herbal teas) has growth-inhibitory and proapoptotic effects associated with suppressed activation of STAT3. We used human Barrett's epithelial and esophageal adenocarcinoma cell lines to determine effects of honokiol on cell number, necrosis, apoptosis, and anchorage-independent growth and to explore STAT3's role in those effects. We determined Ras activity and expression of phosphorylated ERK1/2, phosphorylated Akt, and phosphorylated STAT3 in the presence or absence of honokiol. Cells were infected with constitutively active Stat3-C to assess effects of honokiol-induced STAT3 inhibition on apoptosis. Honokiol decreased cell number and increased necrosis and apoptosis in transformed Barrett's cells, but not in nontransformed cells. In adenocarcinoma cells, honokiol also increased necrosis and apoptosis and decreased anchorage-independent growth. Within 30 min of honokiol treatment, transformed Barrett's cells decreased expression of phosphorylated STAT3; decreases in Ras activity and phosphorylated ERK1/2 expression were detected at 24 h. Infection with Stat3-C significantly reduced apoptosis after honokiol treatment. Honokiol causes necrosis and apoptosis in transformed Barrett's and esophageal adenocarcinoma cells, but not in nontransformed Barrett's cells, and the proapoptotic effects of honokiol are mediated by its inhibition of STAT3 signaling. These findings suggest a potential role for targeting the intrinsic inflammatory pathways as a therapeutic strategy to prevent Barrett's carcinogenesis.

Distribution of body fat and its influence on esophageal inflammation and dysplasia in patients with Barrett's esophagus

BACKGROUND & AIMS

Increased waist circumference and visceral fat are associated with increased risk of Barrett's esophagus (BE) and esophageal adenocarcinoma. This association might be mediated by mechanical and endocrine mechanisms. We investigated the distribution of fat in subjects with BE and its association with esophageal inflammation and dysplasia.

METHODS

We collected data from 50 BE cases and 50 controls (matched for age and sex, identified from a radiology trauma database) seen at the Mayo Clinic in 2009. Abdominal (subcutaneous and visceral) and gastroesophageal junction (GEJ) fat area was measured using computed tomography with standard techniques. Esophageal inflammation (based on a histologic score) and dysplasia grade were assessed from esophageal biopsies of BE cases by a gastrointestinal pathologist. Conditional logistic regression was used to assess the association of body fat depot area with BE status, esophageal inflammation, and dysplasia.

RESULTS

All BE subjects had controlled reflux symptoms without esophagitis, based on endoscopy. The GEJ fat area (odds ratio [OR], 6.0; 95% confidence interval [CI], 1.3-27.7; P = .02), visceral fat area (OR, 4.9; 95% CI, 1.0-22.8; P = .04), and abdominal circumference (OR, 9.1; 95% CI, 1.4-57.2; P = 0.02) were associated with BE, independent of body mass index (BMI). The subcutaneous fat area was not associated with BE. Visceral and GEJ fat were significantly greater in BE subjects with esophageal inflammation (compared with those without, P = .02) and high-grade dysplasia (compared with those without, P = .01), independent of BMI.

CONCLUSIONS

GEJ and visceral fat are associated with BE, and with increased esophageal inflammation and high-grade dysplasia in BE subjects, independent of BMI. Visceral fat therefore might promote esophageal metaplasia and dysplasia.

Vital-dye enhanced fluorescence imaging of GI mucosa: metaplasia, neoplasia, inflammation

BACKGROUND

Confocal endomicroscopy has revolutionized endoscopy by offering subcellular images of the GI epithelium; however, the field of view is limited. Multiscale endoscopy platforms that use widefield imaging are needed to better direct the placement of high-resolution probes.

DESIGN

Feasibility study.

OBJECTIVE

This study evaluated the feasibility of a single agent, proflavine hemisulfate, as a contrast medium during both widefield and high-resolution imaging to characterize the morphologic changes associated with a variety of GI conditions.

SETTING

The University of Texas MD Anderson Cancer Center, Houston, Texas, and Mount Sinai Medical Center, New York, New York. PATIENTS, INTERVENTIONS, AND MAIN OUTCOME MEASUREMENTS: Resected specimens were obtained from 15 patients undergoing EMR, esophagectomy, or colectomy. Proflavine hemisulfate, a vital fluorescent dye, was applied topically. The specimens were imaged with a widefield multispectral microscope and a high-resolution microendoscope. The images were compared with histopathologic examination.

RESULTS

Widefield fluorescence imaging enhanced visualization of morphology, including the presence and spatial distribution of glands, glandular distortion, atrophy, and crowding. High-resolution imaging of widefield abnormal areas revealed that neoplastic progression corresponded to glandular heterogeneity and nuclear crowding in dysplasia, with glandular effacement in carcinoma. These widefield and high-resolution image features correlated well with the histopathologic features.

LIMITATIONS

This imaging approach must be validated in vivo with a larger sample size.

CONCLUSIONS

Multiscale proflavine-enhanced fluorescence imaging can delineate epithelial changes in a variety of GI conditions. Distorted glandular features seen with widefield imaging could serve as a critical bridge to high-resolution probe placement. An endoscopic platform combining the two modalities with a single vital dye may facilitate point-of-care decision making by providing real-time, in vivo diagnoses.

Prevalence of Barrett esophagus in first-degree relatives of patients with esophageal adenocarcinoma

AIM

The aim of this study is to determine the prevalence of Barrett esophagus (BE) in first-degree relatives of patients with esophageal adenocarcinoma (EAC) and Barrett high-grade dysplasia (HGD).

METHODS

After Institutional Review Board approval, first-degree relatives of patients with EAC/HGD underwent unsedated ultrathin transnasal endoscopy (UUTNE) with biopsy. BE was suspected if any salmon-colored epithelial tongues were seen above the gastroesophageal junction. A diagnosis of BE was made only if biopsy from these areas confirmed columnar-lined epithelium with intestinal metaplasia.

RESULTS

From 23 families, 47 first-degree relatives underwent ultrathin transnasal endoscopy and 1 patient underwent routine upper endoscopy with sedation as part of this study. The mean age of cases was 44.4 years. All patients tolerated the procedure well and there were no procedure-related complications. BE was suspected in 16 (34%) patients and confirmed in 13 of 16 (27.7%) patients. There were 4 long segments (>3 cm) and 9 short segments (<3 cm) of BE.

CONCLUSION

There is a significantly higher than expected prevalence of BE in first-degree relatives of patients with EAC/HGD. This should be taken in to consideration to develop further screening guidelines. Further work is needed to confirm these findings. Unsedated transnasal endoscopy is a safe and well-tolerated method for BE screening.

Barrett's esophagus: endoscopic treatments II

The following on endoscopic treatments of Barrett's esophagus includes commentaries on animal experiments on cryotherapy; indications for cryotherapy, choice of dosimetry, number of sessions, and role in Barrett's esophagus and adenocarcinoma; recent technical developments of RFA technology and long-term effects; the comparative effects of diverse ablation procedures and the rate of recurrence following treatment; and the indications for treatment of dysplasia and the role of radiofrequency ablation.

Deoxycholic acid causes DNA damage while inducing apoptotic resistance through NF-κB activation in benign Barrett's epithelial cells

Gastroesophageal reflux is associated with adenocarcinoma in Barrett's esophagus, but the incidence of this tumor is rising, despite widespread use of acid-suppressing medications. This suggests that refluxed material other than acid might contribute to carcinogenesis. We looked for potentially carcinogenetic effects of two bile acids, deoxycholic acid (DCA) and ursodeoxycholic acid (UDCA), on Barrett's epithelial cells in vitro and in vivo. We exposed Barrett's (BAR-T) cells to DCA or UDCA and studied the generation of reactive oxygen/nitrogen species (ROS/RNS); expression of phosphorylated H2AX (a marker of DNA damage), phosphorylated IkBα, and phosphorylated p65 (activated NF-κB pathway proteins); and apoptosis. During endoscopy in patients, we took biopsy specimens of Barrett's mucosa before and after esophageal perfusion with DCA or UDCA and assessed DNA damage and NF-κB activation. Exposure to DCA, but not UDCA, resulted in ROS/RNS production, DNA damage, and NF-κB activation but did not increase the rate of apoptosis in BAR-T cells. Pretreatment with N-acetyl-l-cysteine (a ROS scavenger) prevented DNA damage after DCA exposure, and DCA did induce apoptosis in cells treated with NF-κB inhibitors (BAY 11-7085 or AdIκB superrepressor). DNA damage and NF-κB activation were detected in biopsy specimens of Barrett's mucosa taken after esophageal perfusion with DCA, but not UDCA. These data show that, in Barrett's epithelial cells, DCA induces ROS/RNS production, which causes genotoxic injury, and simultaneously induces activation of the NF-κB pathway, which enables cells with DNA damage to resist apoptosis. We have demonstrated molecular mechanisms whereby bile reflux might contribute to carcinogenesis in Barrett's esophagus.

Detection of intestinal metaplasia after successful eradication of Barrett's Esophagus with radiofrequency ablation

BACKGROUND

Radiofrequency ablation (RFA) is an effective means of eradicating Barrett's esophagus (BE), both with and without associated dysplasia. Several studies have documented high initial success rates with RFA. However, there is limited data on IM detection rates after eradication.

AIMS

To determine the rate of detection of intestinal metaplasia (IM) after successful eradication of Barrett's esophagus.

METHODS

BE patients with and without dysplasia who had undergone RFA were retrospectively identified. Only those who had complete eradication as documented on the initial post-ablation endoscopy, and had minimum two surveillance endoscopies, were included in the analyses. Clinical, demographic, and endoscopic data were collected. Cumulative incidence of IM detection was calculated by the Kaplan-Meier method.

RESULTS

Forty-seven patients underwent RFA and had complete eradication of Barrett's epithelium. The majority of patients were male (76.6%), and the mean age was 64.2 years. The cumulative incidence of newly detected IM at 1 year was 25.9% (95% CI 15.1-42.1%). Dysplasia was detected at the time of recurrence in four patients, and all cases were detected at the GE junction in the absence of visible BE. Patients with recurrent IM had longer baseline segments of BE (median, 4 cm vs. 2 cm, p = 0.03).

CONCLUSIONS

The rate of detection of new IM is high in patients who have undergone successful eradication of BE by RFA. Additionally, dysplasia can recur at the GE junction in the absence of visible BE. Future studies are warranted to identify those patients at increased risk for the development of recurrent intestinal metaplasia.

Smoking and Barrett's esophagus in women who undergo upper endoscopy

BACKGROUND

Cigarette use is associated with esophageal adenocarcinoma, and cross-sectional studies suggest an association between smoking and Barrett's esophagus.

AIMS

We sought to examine prospectively the effect of smoking on the risk for Barrett's esophagus.

METHODS

This was a prospective cohort study among 20,863 women within the Nurses' Health Study who underwent upper gastrointestinal endoscopy for any reason between 1980 and 2006. We assessed the association between smoking and pathologically-confirmed Barrett's esophagus (n = 377). Self-reported data on smoking and potential confounding variables were collected from biennial questionnaires.

RESULTS

Compared with women who never smoked, former smokers of 1-24 cigarettes/day had a multivariate odds ratio for Barrett's esophagus of 1.25 (95% CI 0.99-1.59), former smokers of ≥ 25 cigarettes/day had a multivariate odds ratio of 1.52 (95% CI 1.04-2.22), current smokers of 1-24 cigarettes/day had a multivariate odds ratio of 0.89 (95% CI 0.54-1.45), and current smokers of ≥ 25 cigarettes/day had a multivariate odds ratio of 0.92 (95% CI 0.34-2.54). The risk for Barrett's esophagus increased significantly with increasing pack-years smoked among former (P = 0.008) but not current smokers (P = 0.99), especially when considering exposure ≥ 25 years before index endoscopy. Results were similar among women reporting regular heartburn/acid-reflux one or more times a week, and were not accounted for by changes in weight.

CONCLUSIONS

Heavy, remote smoking is associated with an increased risk for Barrett's esophagus. This finding suggests a long latency period between exposure and development of the disease, even after discontinuation of smoking.

Cancer-related inflammation and Barrett's carcinogenesis: interleukin-6 and STAT3 mediate apoptotic resistance in transformed Barrett's cells

Cancer-related inflammation recently has been proposed as a major physiological hallmark of malignancy. Some genetic alterations known to promote cellular proliferation and induce malignant transformation also may participate in an intrinsic inflammatory pathway that produces a cancer-promoting inflammatory microenvironment. Little is known about this intrinsic inflammatory pathway in Barrett's esophagus. We have used a series of nontransformed and transformed human Barrett's epithelial cell lines developed in our laboratory to explore the potential contribution of interleukin (IL)-6 and signal transducer and activator of transcription (STAT3) (key molecules in the intrinsic inflammatory pathway) to Barrett's carcinogenesis. We determined IL-6 mRNA expression and protein secretion and protein expression of activated phospho-STAT3 and its downstream target myeloid cell leukemia (mcl)-1 (Mcl-1). We used an IL-6 blocking antibody and two JAK kinase inhibitors (AG490 and JAK inhibitor I) to assess whether STAT3 activation is IL-6 dependent. We also used small interfering RNAs (siRNAs) to STAT3 and Mcl-1 to assess effects of STAT3 pathway inhibition on apoptosis. Phospho-STAT3 was expressed only by transformed Barrett's cells, which also exhibited higher levels of IL-6 mRNA and of IL-6 and Mcl-1 proteins than nontransformed Barrett's cells. STAT3 phosphorylation could be blocked by IL-6 blocking antibody and by AG490 and JAK inhibitor I. In transformed Barrett's cells, rates of apoptosis following exposure to deoxycholic acid were significantly increased by transfection with siRNAs for STAT3 and Mcl-1. We conclude that activation of the IL-6/STAT3 pathway in transformed Barrett's epithelial cells enables them to resist apoptosis. These findings demonstrate a possible contribution of the intrinsic inflammatory pathway to carcinogenesis in Barrett's esophagus.

The integrity of the esophageal mucosa. Balance between offensive and defensive mechanisms

Heartburn is the most common and characteristic symptom of gastroesophageal reflux disease. It ultimately results from contact of refluxed gastric acid with nociceptors within the esophageal mucosa and transmission of this peripheral signal to the central nervous system for cognition. Healthy esophageal epithelium provides an effective barrier between refluxed gastric acid and esophageal nociceptors; but this barrier is vulnerable to attack and damage, particularly by acidic gastric contents. How gastric acid is countered by defensive elements within the esophageal mucosa is a major focus of this discussion. When the defense is successful, the subject is asymptomatic and when unsuccessful, the subject experiences heartburn. Those with heartburn commonly fall into one of three endoscopic types: nonerosive reflux disease, erosive esophagitis and Barrett's esophagus. Although what determines endoscopic type remains unknown; it is proposed herein that inflammation plays a key, modulating role.

Acid-induced p16 hypermethylation contributes to development of esophageal adenocarcinoma via activation of NADPH oxidase NOX5-S

Inactivation of tumor suppressor gene p16 may play an important role in the progression from Barrett's esophagus (BE) to esophageal adenocarcinoma (EA). Hypermethylation of p16 gene promoter is an important mechanism inactivating p16. However, the mechanisms of p16 hypermethylation in EA are not known. Therefore, we examined whether acid increases methylation of p16 gene promoter and whether NADPH oxidase NOX5-S mediates acid-induced p16 hypermethylation in a Barrett's cell line BAR-T and an EA cell line OE33. We found that NOX5-S was present in BAR-T and OE33 cells. Acid-induced increase in H(2)O(2) production and cell proliferation was significantly reduced by knockdown of NOX5-S. Exogenous H(2)O(2) remarkably increased p16 promoter methylation and cell proliferation. In addition, acid treatment significantly increased p16 promoter methylation and decreased p16 mRNA level. Knockdown of NOX5-S significantly increased p16 mRNA, inhibited acid-induced downregulation of p16 mRNA, and blocked acid-induced increase in p16 methylation and cell proliferation. Conversely, overexpression of NOX5-S significantly decreased p16 mRNA and increased p16 methylation and cell proliferation. In conclusion, NOX5-S is present in BAR-T cells and OE33 cells and mediates acid-induced H(2)O(2) production and cell proliferation. NOX5-S is also involved in acid-induced hypermethylation of p16 gene promoter and downregulation of p16 mRNA. It is possible that acid reflux present in BE patients may activate NOX5-S and increase production of reactive oxygen species, which in turn increase p16 promoter methylation, downregulate p16 expression, and increase cell proliferation, thereby contributing to the progression from BE to EA.

Aberrant epithelial-mesenchymal Hedgehog signaling characterizes Barrett's metaplasia

BACKGROUND & AIMS

The molecular mechanism underlying epithelial metaplasia in Barrett's esophagus remains unknown. Recognizing that Hedgehog signaling is required for early esophageal development, we sought to determine if the Hedgehog pathway is reactivated in Barrett's esophagus, and if genes downstream of the pathway could promote columnar differentiation of esophageal epithelium.

METHODS

Immunohistochemistry, immunofluorescence, and quantitative real-time polymerase chain reaction were used to analyze clinical specimens, human esophageal cell lines, and mouse esophagi. Human esophageal squamous epithelial (HET-1A) and adenocarcinoma (OE33) cells were subjected to acid treatment and used in transfection experiments. Swiss Webster mice were used in a surgical model of bile reflux injury. An in vivo transplant culture system was created using esophageal epithelium from Sonic hedgehog transgenic mice.

RESULTS

Marked up-regulation of Hedgehog ligand expression, which can be induced by acid or bile exposure, occurs frequently in Barrett's epithelium and is associated with stromal expression of the Hedgehog target genes PTCH1 and BMP4. BMP4 signaling induces expression of SOX9, an intestinal crypt transcription factor, which is highly expressed in Barrett's epithelium. We further show that expression of Deleted in Malignant Brain Tumors 1, the human homologue of the columnar cell factor Hensin, occurs in Barrett's epithelium and is induced by SOX9. Finally, transgenic expression of Sonic hedgehog in mouse esophageal epithelium induces expression of stromal Bmp4, epithelial Sox9, and columnar cytokeratins.

CONCLUSIONS

Epithelial Hedgehog ligand expression may contribute to the initiation of Barrett's esophagus through induction of stromal BMP4, which triggers reprogramming of esophageal epithelium in favor of a columnar phenotype.

Endoscopic ablation of Barrett's esophagus using the Halo system

There is increasing interest in the endoscopic treatment of Barrett's esophagus. Endoscopic treatment has been utilized for many years, but in the past, no specific method has emerged as an appealing treatment option with appropriate safety, efficacy and ease of treatment for both patients and physicians. Recently there has been a growing literature related to the endoscopic ablation of Barrett's esophagus using radiofrequency ablation (RFA) (Halo system). In order to discuss when RFA is indicated for Barrett's, one needs to know: (1) What is the 'histology' of the Barrett's? Does the patient have intestinal metaplasia, low-grade dysplasia, high-grade dysplasia or intramucosal carcinoma? (2) What are the endoscopic options to be considered as opposed to RFA? What are the advantages and disadvantages of each? (3) What additional variables need to be examined?

High-resolution imaging in Barrett's esophagus: a novel, low-cost endoscopic microscope

BACKGROUND

This report describes the clinical evaluation of a novel, low-cost, high-resolution endoscopic microscope for obtaining fluorescent images of the cellular morphology of the epithelium of regions of the esophagus with Barrett's metaplasia. This noninvasive point imaging system offers a method for obtaining real-time histologic information during endoscopy.

OBJECTIVE

The objective of this study was to compare images taken with the fiberoptic endoscopic microscope with standard histopathologic examination.

DESIGN

Feasibility study.

SETTING

The University of Texas M.D. Anderson Cancer Center Department of Gastroenterology. PATIENTS, INTERVENTIONS, AND MAIN OUTCOME MEASUREMENTS: The tissue samples studied in this report were obtained by endoscopic resection from patients with previous diagnoses of either high-grade dysplasia or esophageal adenocarcinoma.

RESULTS

Three distinct tissue types were observed ex vivo with the endoscopic microscope: normal squamous mucosa, Barrett's metaplasia, and high-grade dysplasia. Squamous tissue was identified by bright nuclei surrounded by dark cytoplasm in an ordered pattern. Barrett's metaplasia could be identified by large glandular structures with intact nuclear polarity. High-grade dysplasia was visualized as plentiful, irregular glandular structures and loss of nuclear polarity. Standard histopathologic examination of study samples confirmed the results obtained by the endoscopic microscope.

LIMITATIONS

The endoscopic microscope probe had to be placed into direct contact with tissue.

CONCLUSIONS

It was feasible to obtain high-resolution histopathologic information using the endoscopic microscope device. Future improvement and integration with widefield endoscopic techniques will aid in improving the sensitivity of detection of dysplasia and early cancer development in the esophagus.

How useful is histologic confirmation of intestinal metaplasia in patients with long-segment Barrett's esophagus?

BACKGROUND

Controversy exists regarding the usefulness of histologic confirmation of intestinal metaplasia in patients with long-segment Barrett's esophagus (LSBE).

OBJECTIVES

To determine the frequency of intestinal metaplasia in patients with LSBE and to establish an optimal biopsy protocol to detect intestinal metaplasia in these patients.

DESIGN AND INTERVENTION

This retrospective, single-center study included consecutive patients with LSBE (defined as ≥1 cm of columnar-lined esophagus). Exclusion criteria included previous surgical repair of the lower esophageal sphincter. Patients were arbitrarily allocated to one of two endoscopic biopsy procedures: endoscopy with 1–4 biopsies taken, or endoscopy with >4 biopsies taken. The number of biopsies taken in the >4 biopsies group was influenced by clinician judgment. All biopsy specimens were histologically assessed using hematoxylin and eosin staining. At least three gastrointestinal pathologists examined each specimen to determine the mucosa type (intestinal metaplasia, cardiac type, fundic type, glandular not otherwise specified, or squamous). Intestinal metaplasia was diagnosed by the presence of goblet cells. Further histologic assessment with standard alcian blue-periodic acid–Schiff staining was performed in a subset of patients who had >6 biopsies taken during endoscopy. At least two pathologists assessed these specimens. Patients were stratified by the number of biopsies taken per endoscopy: 1–4, 5–8, 9–12, 13–16 and >16.

OUTCOME MEASURES

The main outcome measures were the detection of intestinal metaplasia, and the frequency of intestinal metaplasia detected according to the number of biopsies taken.

RESULTS

In total, 125 patients (mean age 65 years [range 41–85 years]) were included, in whom 296 endoscopies were performed and 1,646 biopsies were taken. Mean follow-up was 25 months. The mean length of a Barrett's esophagus segment was 4 cm (range 1–11 cm). Intestinal metaplasia was present in 80 patients (64%); 150 endoscopies (51%) revealed intestinal metaplasia and 557 biopsies (34%) contained foci of intestinal metaplasia. The mean percentage of patients in whom intestinal dysplasia was detected was significantly greater in the group that had 5–8 biopsies taken per endoscopy than the group that had 1–4 biopsies taken per endoscopy: 67.9% (95% CI 64–71.8%) and 34.6% (95% CI 32–37.6%), respectively; P <0.001. There was no significant difference in the mean percentage of intestinal metaplasia detected between patients who had 5–8 biopsies taken per endoscopy, and those who had 9–12, and 13–16 biopsies taken per endoscopy; the diagnostic yield of intestinal metaplasia was 100% if >16 biopsies were taken per endoscopy. Standard alcian blue-periodic acid–Schiff staining resulted in a change in diagnosis for 5 of 92 patients (5.4%) who underwent this assessment. Increasing age was associated with a significant reduction in the risk of detecting intestinal metaplasia.

CONCLUSION

A minimum of eight random biopsies are required to be taken per endoscopy to diagnose intestinal metaplasia in patients with LSBE.

Sulindac prevents esophageal adenocarcinomas induced by gastroduodenal reflux in rats

PURPOSE

It is known that cyclooxygenase (COX)-2 expression is increased in Barrett's esophagus and esophageal adenocarcinomas. We studied COX-2 expression and the effect sulindac has on the genesis of Barrett's esophagus and adenocarcinoma in rats undergoing esophagogastroduodenal anastomosis (EGDA).

MATERIALS AND METHODS

Fifty-one rats were divided into a control group (n=27), a 500 ppm sulindac-treated group (n=15) and 1000 ppm sulindac-treated group (n=9). Randomly selected rats were killed by diethyl ether inhalation at 20 and 40 weeks after surgery.

RESULTS

At 40 weeks, rats treated with 1000 ppm sulindac showed narrower esophageal diameter and milder inflammation than the control rats. At 40 weeks, the incidence of Barrett's esophagus was similar between control and sulindac-treated groups, but the incidence of adenocarcinoma was significantly lower in the 1000 ppm sulindac-treated group than either the control or 500 ppm sulindac-treated groups. COX-2 was significantly increased in the lower esophagus of control rats killed at 40 weeks. Cyclin D1 expression was negligible in the sulindac- treated group compared with the control group.

CONCLUSION

We suggest that the chemopreventive effect of sulindac is related to decreased COX-2 and cyclin D1 expression, which may be influenced by reduced inflammation.

Zoning of mucosal phenotype, dysplasia, and telomerase activity measured by telomerase repeat assay protocol in Barrett's esophagus

Glandular dysplasia in Barrett's esophagus may regress spontaneously but can also progress to cancer. The human telomerase RNA template and the human telomerase reverse transcriptase enzyme which do not, of themselves, correlate strongly with telomerase activity, are too often overexpressed in Barrett's dysplasia to predict individual cancer risk. This study relates telomerase activity, mucosal phenotype, and dysplasia in Barrett's esophagus. Biopsies (n = 256) from squamous esophagus, columnar-lined esophagus every 2 cm, esophago-gastric junction, gastric body, and antrum from 32 patients with long-segment Barrett's esophagus were evaluated by telomerase repeat assay protocol (TRAP). Three biopsies for histology (n = 794) were simultaneously taken at each anatomical level. These and all prior and subsequent biopsies (n = 1917) were reviewed for mucosal phenotypes and dysplasia severity. Intestinal-type Barrett's mucosa was present at all levels in Barrett's esophagus. At least one Barrett's biopsy was TRAP(+) in 22 of 32 patients. TRAP positivity of intestinal-type Barrett's mucosa increased distally, possibly as a consequence of mucosal exposure to acid or bile reflux. Native gastric mucosa was rarely TRAP(+) (1/31 corpus, 2/32 antrum), whereas native squamous mucosa usually was TRAP(+) (31/32). Dysplasia almost always involved intestinal-type Barrett's mucosa (85/87; P <.00001), without evidence of proximal-distal zoning. TRAP could be positive without dysplasia and negative in extensive, even high-grade, dysplasia. TRAP activity merits evaluation as a candidate biomarker for increased risk of persistent dysplasia and cancer progression in Barrett's esophagus.

Transcriptional analyses of Barrett's metaplasia and normal upper GI mucosae

Over the last two decades, the incidence of esophageal adenocarcinoma (EA) has increased dramatically in the US and Western Europe. It has been shown that EAs evolve from premalignant Barrett's esophagus (BE) tissue by a process of clonal expansion and evolution. However, the molecular phenotype of the premalignant metaplasia, and its relationship to those of the normal upper gastrointestinal (GI) mucosae, including gastric, duodenal, and squamous epithelium of the esophagus, has not been systematically characterized. Therefore, we used oligonucleotide-based microarrays to characterize gene expression profiles in each of these tissues. The similarity of BE to each of the normal tissues was compared using a series of computational approaches. Our analyses included esophageal squamous epithelium, which is present at the same anatomic site and exposed to similar conditions as Barrett's epithelium, duodenum that shares morphologic similarity to Barrett's epithelium, and adjacent gastric epithelium. There was a clear distinction among the expression profiles of gastric, duodenal, and squamous epithelium whereas the BE profiles showed considerable overlap with normal tissues. Furthermore, we identified clusters of genes that are specific to each of the tissues, to the Barrett's metaplastic epithelia, and a cluster of genes that was distinct between squamous and non-squamous epithelia.

Indomethacin-induced apoptosis in esophageal adenocarcinoma cells involves upregulation of Bax and translocation of mitochondrial cytochrome C independent of COX-2 expression

The prolonged use of nonsteroidal anti-inflammatory drugs (NSAIDs) has been shown to exert a chemopreventive effect in esophageal and other gastrointestinal tumors. The precise mechanism by which this occurs, however, is unknown. While the inhibition of COX-2 as a potential explanation for this chemopreventive effect has gained a great deal of support, there also exists evidence supporting the presence of cyclooxygenase-independent pathways through which NSAIDs may exert their effects. In this study, immunohistochemical analysis of 29 Barrett's epithelial samples and 60 esophageal adenocarcinomas demonstrated abundant expression of the COX-2 protein in Barrett's epithelium, but marked heterogeneity of expression in esophageal adenocarcinomas. The three esophageal adenocarcinoma cell lines, Flo-1, Bic-1, and Seg-1, also demonstrated varying expression patterns for COX-1 and COX-2. Indomethacin induced apoptosis in all three cell lines, however, in both a time- and dose-dependent manner. In Flo-1 cells, which expressed almost undetectable levels of COX-1 and COX-2, and in Seg-1, which expressed significant levels of COX-1 and COX-2, indomethacin caused upregulation of the pro-apoptotic protein Bax. The upregulation of Bax was accompanied by the translocation of mitochondrial cytochrome c to the cytoplasm, and activation of caspase 9. Pre-treatment of both cell lines with the specific caspase 9 inhibitor, z-LEHD-FMK, as well as the broad-spectrum caspase inhibitor, z-VAD-FMK, blocked the effect of indomethacin-induced apoptosis. These data demonstrate that induction of apoptosis by indomethacin in esophageal adenocarcinoma cells is associated with the upregulation of Bax expression and mitochondrial cytochrome c translocation, and does not correlate with the expression of COX-2. This may have important implications for identifying new therapeutic targets in this deadly disease.

Immunohistochemical localization of glutathione S-transferase alpha and pi in human esophageal squamous epithelium, Barrett's epithelium and carcinoma

High tissue levels of glutathione S-transferases (GSTs), a family of detoxification enzymes, are inversely correlated with cancer risk in the human gastrointestinal tract. Patients with Barrett's esophagus, wherein squamous epithelium is replaced by columnar epithelium, have an increased risk for developing esophageal adenocarcinoma. Biochemical analyses revealed that Barrett's epithelium contains lower levels of GST enzyme activity as well as some GST isoforms, as compared with squamous epithelium. So far, little information on the immunohistochemical distribution of the GST alpha and pi isoforms in normal squamous epithelium, in Barrett's metaplastic epithelium or in adeno- and squamous cell carcinomas of the esophagus is available. Tissues were fixed in formalin and embedded in paraffin. Three 4 microm thick sections were used for hematoxylin and eosin staining and for immunostaining with antibodies against GST alpha and pi. GST alpha and pi were seen in normal squamous epithelium (0% and 75%, respectively), Barrett's epithelium (75% and 100%), adenocarcinoma (25% and 100) and squamous cell carcinoma (27% and 91%). Staining was mainly cytoplasmic, though some nuclear staining with the GST pi antibody was apparent. The varying expression of GST alpha and pi in normal and (pre)neoplastic esophagus may have consequences for the treatment of these diseases and may contribute to an understanding of the development of these esophageal disorders.

Low glutathione and glutathione S-transferase levels in Barrett's esophagus as compared to normal esophageal epithelium

Patients with Barrett's esophagus, wherein squamous epithelium has been replaced by columnar epithelium, have an increased risk for developing esophageal adenocarcinoma as compared to the general population. Glutathione S-transferase (GST), a family of detoxification enzymes consisting of class alpha, mu, pi, and theta isoforms, is involved in detoxification of carcinogens and low levels of these enzymes correlated with high cancer risk. We have now compared GST enzyme activity, GST isoenzyme composition and glutathione (GSH) content of Barrett's mucosa with that of adjacent normal squamous epithelium. Biopsy specimens of 98 patients with Barrett's esophagus were taken from both Barrett's and adjacent normal squamous epithelium. GST enzyme activity towards 1-chloro-2,4-dinitrobenzene was measured, and GST isoenzyme levels were determined by densitometrical analyses of western blots after immunodetection with monoclonal antibodies. Total GSH content was determined by high-performance liquid chromatography after conjugation with monobromobimane. Wilcoxon's signed rank test and Spearman correlation analyses were used for statistical evaluation. As compared with adjacent normal squamous epithelium, GST enzyme activity in Barrett's epithelium was reduced by 35%, and GST mu, GST pi and GSH levels were reduced by 24%, 30%, and 63%, respectively. However, the minor GST alpha and GST theta levels were higher in Barrett's epithelium (by 625% and 33%, respectively). High levels of GSH and GSTs in general are correlated with protection against cellular or cytogenetic damage. The observed reduction in GSTs and GSH in Barrett's epithelium may therefore contribute to the increased cancer risk in this tissue.